If the manufacturer left the upgrade feature unlocked, you can update via USB.

There are two ways software was handled for this specific board in 2021.

Because this board uses One-Time Programmable memory, if a software update fails or you flash the wrong firmware:

If you cannot locate the exact 2021 software package, consider these alternatives:

If you are working with this software or file in a technical or embedded systems context, here is a generic template for an informational article you could adapt or complete with actual details from your documentation or source:

If you can provide:

…I can give you a specific, accurate article instead of a placeholder. Would you like that?

For a 2021 release, such software might have included:

The 1506L boards come with different remote codes (NEC, RC5). If you flash new software and the remote stops working: